Designation-plug for telephone-switchboards.



PATENTED JAN. 7, 1908.

v A. H. ADAMS.

DESIGNATION PLUG FOR TELEPHONE SWITGHBOARDS.

APPLICATION FILED MAY 31, 1907- lllllli www/7@ 1HE N Rius PETERS co., WASHINGTON. u,

UNITED STATES PATENT OFFICE.

ARTHUR II. ADAMS, OF ANTWERI), BELGIUM, ASSIGNOR TO WESTERN ELECTRIC COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

DESIGNATION-PLUG FOR TE LEPHONE-SWITCHBOARDS.

Speceation of Letters Patent.

Patented Jan. 7, 1908.

Application tiled May 3l. 1907. Serial No. 376.684.

To all whom it may concern:

Be it known that I, ARTHUR H. Anims, citizen of the United States, residing at Antwerp, in the country of Belgium, have 5 invented a certain new and useful Improvement in Designation-Plugs for Telephone- Switchboards, of which the following' is a full clear, concise, and exact description.

My invention relates to designation plugs or plates for telephone switchboards, and its object is to provide a plug which is of simple construction, which can be readily inserted in or removed from a ack,- and which, when in position, will be 'llush with the surface of the strip of jacks.

Plugs or plates are commonly used in multiple jacks of telephone switchboards for designation purposes. For example, if service 'to a particular subscriber is discontinued, a plug inserted in the multiple jacks of his line as an indication of the fact to the operator. Such a plug, by its color, or by some-mark it mayr bear, is used to indicate various conditions. lleretofore such plugs have ordinarily been constructed so as to project in front of the strip in order that they might be readily grasped and thus easily removed. By my invention the feature of accessibility for removal purpose is retained, whether or not theI plug' projects outward, and the withdrawal of said plug greatly facilitated.

My invention consists in so shaping the inner end of the plug that when inserted in one position it is securely held in place, and when slightly turned it is released and may be readilywithdrawn.

My invention may be more readily understood by reference to the accompanying drawing, in which,

Figure l is a front fragmentary view of a strip of jacks showing designation plugs in position; Fig'. 2 is a vertical section through one of the jacks, showing the manner in which the plug' is held in place. Fig. is a view somewhat similar to that of F ig. 2, but showing' the manner in which the plug'is released; Fig. el is a perspective view of the plug of my invention; and Fig'. 5 is a view similar to Fig. 2, of a modified form of plug'.

The plug l may be provided with a head 2 similar to the ordinary slotted head of a screw. The other end of the plue' is cut away on one side to provide a flat surface 3. Diametrically opposite the surface 3 the plug is beveled towards its tip to produce a cam surface Ll.

To insert thc plug 1 in a jack 5, it is merely pushed therein, the spring 6 engaging the llat surface 3, and securely holding the plug or plate with its front vface flush with the face of the strip, as indicated in Fig. 2. To remove the plug 1 it is merely necessary to rotate the same one-half of a revolution, bringing the be"` eled surface l beneath the spring 6. Said spring, by its resiliency, then pushes the plug onward a slight distance, as indicated in ,F ig. 3, whereupon the plug may be readily grasped and withdrawn.

In F ig'. 5 I have shown a modified form of plug in which the head 2 projects slightly beyond the face of the strip and in which the front end of the surface 3 is beveled in order that the spring 6 may more readily ride onto the flat surface C3.

lla'ving described my invention, I claim:

l. The combination with a spring ack, of a designation plug having a surface against which a spring of said jack is adapted to bear to hold said plug in place, and a cam surface adapted when the4 plug is turned from its inserted position to coperate with said spring to release said plug.

2. The combination with a spring ack, of a designation plug' having a 'flat surface on one side against which a spring of said jack is adapted to bear to hohl said plug in place, and a beveled surface upon its opposite side against which said spring is adapted to bear, upon the rotation of said plug from its inserted position.

A designation plug comprising' a cylindrical body portion having one side cut away at its end to provide a flat surface, and having the opposing side beveled at the end of the plug towards said llat surface.

Ll. A designation plug comprising a cylindrical body portion having a slotted head upon one end, said body portion being cut away at its opposite end upon one side to form a flat surface, and having the opposite side beveled at the end of the plug.

In witness whereof, I, hereunto subscribe my name this fourteenth day of May A. D., 1907.

ARTHUR I-I. ADAMS.

W'itnesses:

I'l. Tuoi; SHERMAN, G. DE LERSY. 

